As a parent of a 27 year old who began aikido when he was 5, I think the benefits were enormous. No matter how long I stay in the dojo and he stays out, I will never have his ukemi. It is part of him, ingrained into his body for most of his life. The philosophy, too. What I had to work hard to get rid of and replace just wasn't ever put into him. The dojo was a wonderful community that helped me raise my child.
Susan